Jupiter
Jupiter has 115 official moons as of August 2026. That number can go up when scientists find more tiny ones. Four of them are huge: Io, Europa, Ganymede, and Callisto.
On this page: the moon count, the four giant moons, faint rings, and what a moon is.
Read the answer below. In Giant, kids can keep asking Jupiter.
Jupiter
NASA and the International Astronomical Union keep the official list. As of August 2026, that list has 115 moons. Telescopes keep spotting tiny ones, so the scoreboard can move. Most of those moons are small and far out. Four of them are famous. They are called the Galilean moons. Galileo spotted them in 1610. If a book says 95 moons, it is not wrong about the past. It is just out of date.
115
Official moons (Aug 2026)
4
Giant Galilean moons
Ganymede
Biggest moon of all
Faint
Dusty rings
They are Jupiter's four biggest companions. Io is covered in volcanoes. It is the most volcanic world we know. Europa hides a huge ocean under ice. That is why NASA sent Europa Clipper. Ganymede is the largest moon in the whole solar system. It is bigger than the planet Mercury. Callisto is farther out and covered in craters. It looks old and icy. Together they are like a mini solar system around Jupiter.
Yes. They are not Saturn's bright ice ribbons. Jupiter's rings are faint and dusty. They are mostly tiny bits knocked off small inner moons. You would not see them easily in a backyard telescope. Saturn wins the postcard. Jupiter wins the moon family.
A moon is a natural object that orbits a planet, a dwarf planet, or even an asteroid. Earth's Moon is one big companion. Jupiter has a crowd. A few are huge worlds. Many are little leftover rocks that got captured. Size is not the test. Orbit is.
In Giant
In Giant, a question about space becomes a conversation. Kids ask how many moons Jupiter has, then keep going.
How many moons do you have?
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